Installation of shingles and other roofing materials on a sloped roof is a difficult job. Roofer's often use strap-on knee pads to protect their knees during roofing installation work. Published U.S. Application No. 2009/0151039 published Jun. 18, 2009 shows a pair of strap-on knee pads for use by roofers, which knee pads are made of a material such as expanded polystyrene and can be strapped to a roofer's lower legs. The pads are tapered to compensate at least in part for the slope of the roof.